Oral Recitation

What is the charge of a proton, neutron, and electron?

• Proton: Positive, Neutron: Neutral, Electron: Negative

• Proton: Neutral, Neutron: Negative, Electron: Positive

• Proton: Negative, Neutron: Positive, Electron: Neutral

Where are protons, electrons, and neutrons located in an atom?

• Electrons are in the nucleus; protons and neutrons orbit the nucleus.

• Protons and neutrons are in the nucleus; electrons orbit the nucleus.

• Protons and electrons are in the nucleus; neutrons orbit the nucleus.

Explain why solids have a definite shape and volume.

• The particles in a solid are tightly packed and vibrate in fixed positions.

• The particles in a solid are free to move around and take the shape of their container.

• Solids have a definite shape and volume because their particles are spread out in the container.

Define physical change. How does it differ from a chemical change?

• A physical change only changes the appearance; a chemical change creates a new substance.

• Physical and chemical changes are the same thing.

• A chemical change is always reversible; a physical change is always irreversible.

Can a physical change be reversed?

• Only with special chemicals

• Yes, often by changing the temperature or pressure.

• Never

What is the Law of Octaves? Who proposed it?

• Atoms have eight energy levels; proposed by Ernest Rutherford.

• Elements have eight electrons in their outer shell: proposed by Niels Bohr.

• Every eighth element has similar properties; proposed by John Newlands.

What is a “triad” in the context of early periodic table development? Who proposed it?

• A group of three elements with similar properties; proposed by Johann Wolfgang Döbereiner.

• A group of three scientists working together; proposed by Mendeleev.

• A set of three rules for organizing elements; proposed by Newlands.

What is the term for a liquid changing into a gas?

• Freezing

• Vaporization

• Melting

What is the periodic table used for?

• Organizes elements and predict their properties based on their position.

• To show the history of chemistry.

• Only to list the names of the elements.

What do elements in the same group have in common?

• The same number of protons.

• The same atomic mass.

• Similar chemical properties and the same number of valence electrons.